Lightning arrester



March 24, 1925.

L.. C. HART LIGHTNING ARRSSTER Filed June 2. 1921 l/VViA/TOR Patented Mar. 24, 1925.

UNITED STATES PATIENT OFFICE-" LESTER c. HART, or CLEVELAND, on'io, ASSIGNOR r0 HLVOLTAGEEQUIPMENT coup PANY, A conronn' w on PENNSYLVANIA.

LIGHTNING ABRESTER.

Application filed June 2,

To all whom ma concern:

Be it knownthat I, LESTER C. Him, a 'citizen'of the United States, and a resident of Cleveland, inthe county of Cuyahoga and State of Ohio, have made a new and useful Invention in Lightning Arresters, of which order to protect the line and the apparatus jpractice to provide a relief circuit to the 20" connected thereto from injury. In'appara-- tus oftlns general character it has been the ground including a horn gap and resistance; The gap prevents anyloss' of current under normal conditions, but when a surge of cur-V rent is imposed upon the line and of such a character that it might injure the line or the apparatus connected thereto, an arc is produced across the gap and the current conducted thronghihilffiifijfl ce to. the ground, such are being broken automatically bythe lengthening of the' arc due to its upward movement on the diverging horns or discharge members at opposite sides of the gap. The normal current in the supply line tends to continue the are after the crest of the surge has passed the ap to the ground and.

it is this current Whic 1 is generally res onsi- -blefor any injury to the resistance in t re re-.

lief circuit. If the gap in the relief circuit is lengthened in order to rzduce' the time which the arc continues, the ensitiveness of the device is reduced since the surge must be built up to a higher point before the arc is made, so that the supply circuit lacks the protection which it would have with a shorter gap.

Itis the purpose ofthe present invention to provide an'arrester which will respond flquickly to surges of moderate "intensity, but

rovide for the which will-at the same time and the power interruption of the arc forme clirrent following and continuing such are in 9, mmum interval of time. These. prim ob ects and others which will more fully appear w ll be more readily under protected 1921. Serial No. 474,475.

carrying the insulators 5, 6 and 7. The in-' sulator 5 carries the horn gap bar 8, the insulator 6 carries the-pair of horn gap bars 9 and 10, while the insulator 7 carries'a fourth horn gap bar 11 in opposition-to the har'lO. The opposing bars 8 and 9 provide one discharge gap while the opposing bars 10 and 11 provide a'second gap, such second gap being relatively much shorter than the 'one between the bars 8 and 9. Between the bar 11 and the wire 12 leading to the ground is a suitable resistance carried bv the casing 13. The bar 8 at the other end paratus is provided with the lead connection 14 by means of which the apparatus is connected to the Intermediate the bars 'o ttlll-l-tyl s il member 15 which maybe termeda flash rod, such member providing a relatively high resistanCe connection between the two bars. This rod may be constructed in variety of ways but preferably consists of a fiber core 16 (Fig. 2) surrounded b a. tubular bar 17 of "porcelain. The upper alf of this bar is pro thin coating 18 of,

vided with a relatively carboruhdum although other material may be used in this coating such as flake metals or small particles of conducting material.

The arr-ester as illustrated and described has a number of advantages as compared with the ordinary lightning arrester, having only the single discharge gap and lacking the flash rod feature.

In the first place it is relatively sensitive.

Theaction is'rapid in that the flash rod promotes the quick formation of an arc across thelonger :gap while the discharge across the shorter gap is rela tively quick because of the short distance, so that the excess voltage on the power line may be relieved in a minimum element of time. The flash rod promotes the formation of the are as a flow of current can pass between the two horn rods' 8 and 9 due to the of the up power circuit which is tq bc'" in the art.

conductivity of the coating on the flash rod and the arc will follow the flow time ,set up since the capacity of the flash rod is of course much below the load imposed by a heavy surge of current such as the 'arrester designed to take care of In the second place the arrests: promotes the return to normalcy as soon as the crest of the surge is past since the relatively long gap between the horn members 8, and 9 causes a quick'break as soon -as"the main intensity of the discharge has passed along.

I As aresultthe power current which follows the surge flows through the resistance 13 a minimum length of time. 'It is the flow of the power currentthrough this resistance which tends to injure the resistance so that a rapid breaking of the power current affordsgreat protection against injury to the arrester. .This rapid return to normal condition not only permits the ariester to take care of sur es which occur close together but also pro ongs the life of .the'arrester for the reason above explained and incident to the reducing of the flow of current through.

V gap also permits static, which on many sys r to theg'round without causing any power it may be easil safely an circuit leading mg a pair 0 tems causes a large percentage of arrester discharges, to drain across the flash rod and arc ,as' t line current will not follow to the ground under these conditions. Another advantage incident to this arrester lies in its adaptability since the design economically mounted with t e average installation, and when in service will not require attention other than the regular inspection that equip ment of this general character is given, the apparatus being relatively free from injury and consequently of'long life for the reasons above set forth.

Other advanta es incident to the construction will be-readi y apparent to those skilled What I claim is:

1. In a lightning arrester, the combination with a power circuit, of a relief or discharge to the ground and comprisdischarge gaps of different length each including a pair of :opposing .'discharge members, and a conductor of relawitha tively high resistance lying in the wider gap and connectin the opposing discharge members of suc gap.

2. In a; lightning arrested,- tlieicombination power circuit, of a relief or. discharge circuit eading to the ground and'c'omprisin a pairof horn gaps ofdifierentlength, an

is such that a conductor .of relatively high resistance lying in the wider gap and connectingthe opposing horns of said gap.

3. In a lightning arrester, the combination with a power circuit, of relief or discharge circuit leading to .the ground and comprising a pair of discharge gaps of different length each comprising a pair of opposing dischar e members-with a rod of insulating materia directly connecting the opposin discharge members of the wider gap, suci rod having a coating of conducting material v 4. In a lightning arrester, the combination with a ower circuit, of relief or discharge circuit eading to the ground and comprising a pair of discharge gaps of different length each comprisin apair of opposing discharge members wit a rod of insulating material directly connecting said discharge members of the wider gap, such rod having a coating of conducting material on the side only ad acent said horns.

5. In a lightning arrester, the combination with a power circuit, of relief or discharge circuit leadin to the ground and comprising a pair 0% discharge gaps of different length each comprising a pair of opposing discharge members, with-a refractory conductor of relatively low ca acity directly connecting the opposing disc arge members of the wider gap.

6. In a lightning'arrester, the combination with a ower circuit, of relief or discharge circuit eadin to the ground and comprising a pair of cm gaps of difierent length,

with a re rectory conductor of relatively low capag'ty directly connecting the opposing discharge members of the wider gap. f In La lightning arrester, a horn gap,

'. comprising two opposing horn rods, and a rod of insulatingi material between such rods having a coating of conducting material connected to said horn rods.

8. In a lightning arrester, a horn gap, comprising two opposing'horn rods, and a rod of insulating material between such rods having a coating of refractory conduct- I ing material connected to said horn rods.

9. In a lightning arrester, a3 l1brn gap, comprising two opposing horn rods}; and a rod of insulating material between such rods having a'coating tively low conductivity connected to said horn rock.

10. In a ligntnmg' arrester, a horn a comprising two opposing horn rods, and a rod of insulating material between such of materialist relarods having a coating of conducting material extending only partially around the:

circumference of the rod.

11. In a lightning arrester, a horn p comprising two opposing horn rods, ah a rod of insulating material between such rods having a coating of conducting material extending only partiall around the circumference of the rod wit the side of the rod remote from the horn rods uncoated.

12. In a lightning arrester, the combination with a power circuit, of a relief or discharge circuit leading to the ground and comprising a pair of ischarge gaps of different length, each includinga pair of opposing discharge members, and a bar of insulating material lyiri in the wider gap between the opposin ischarge members of such gap, and provided with a thin coating of carborundum.

13. In a lightning arrester, the combination with a power circuit, of a relief or discharge circuit leading to the ground and comprising a pair of discharge gaps of different length, each including a pair of opposing discharge members, and a bar of insulating material lying in the wider gap between the opposing scharge members of such gap, and consisting of material.

14. In a lighting arr-ester, a discharge circuit leading to the ground and havin a discharge gap) therein, and a rod of insu atin material ridging the gap and provided with a thin coatin of carborundum.

15. In a. lightning arrester, a discharge circuit leading to the ground and havin a discharge ga therein, and a rod of insufating material ridging the gap and rovided with a thin coating consisting of lihely divided conducting material.

In testimony whereof, I have hereunto subscribed my name this 27th day of May,

LESTER C. HART.

lprovided with a thin coating ne particles of conducting Witnesses M. EPSTEIN, W. GACK. 

